Study On The Solvent Extraction Of The Low Rank Coal And Its Application In Coal-blending Coking

This is a new idea of studying the low rank coal resources. However, the mechanism of low rank coal extraction, optimization of process conditions and application of extracts are still in researching phase.Surrounding application of coal extract and various factors which Coal rank, type of solven and extraction temperature in the extraction, experimental results show that the extraction rate could be higher when used medium rank coal, which the extraction rate can be reached 42.56%, when Zhao Ge Zhuang fat coal was extracted in wash oil. The extraction temperature was 300℃ and the constant temperature condition lasted one hour. The extraction rate was increased to a maximum under 360℃. It was found that solvent which was polar and with abilities of donor hydrogen will have a better effect on extraction. When N-methylpyrrolidone as extraction solvent at 360℃ for lignite, the extraction rate can be reach to 50%. Experiments of extraction with mixed solvent, the nonpolar solvent-based extraction agent added polarity, ketones and amines like hydrogen donor solvent, which has a synergistic effect on the extraction. Added solvents of chain, alcohol amines, alcohol has no significant effect on the extraction. The proportion of co-solvent should be controlled to 10% as far as possible.The elemental analysis, IR and 13 CNMR were used for studying the properties of extract. The H/C value was higher than that of raw coal in extract. Extraction has good effect on deashing, deoxidation and desulfurization of coal. The study of coking coal blend of extracts, the proximate analysis index, caking index, Audiberts-Arnu dilatation and Gieseler fluidity were used for the mechanism of Coking coal blending.Thermal reactivity, strength after reaction and scanning electron microscopy were used for evluating the thermal properties and the pore structure of coke. During coking coal blending the thermal properties of coke and coal were improved significantly. Under the premise of coke thermal property, can match the 5% of the lignite for coking.